HP 41C / issue to turn it on

[Bruce Larrabee]

I'd like to second the zebra strip hypothesis. There are many different types of zebra strips in the HP41s though. If it is the gold one try very carefully removing it and the plastic frame below it. Clean the strip carefully (It is very fragile).
Also it will often be fixed by sanding 0.010 inches off of the frame. (From 0.060 to 0.050 in thickness.) If it is another type it may need to be replaced.